// Copyright (C) 2008  Lukas Lalinsky
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License along
// with this program; if not, write to the Free Software Foundation, Inc.,
// 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

#include <QGraphicsScene>
#include <QDebug>
#include "databasetable.h"
#include "databasemodel.h"
#include "column.h"

DatabaseTable::DatabaseTable(QGraphicsItem *parent)
	: DatabaseModelItem(parent)
{
	setFlag(ItemIsMovable);
	setFlag(ItemIsSelectable);
	m_name = "Table";
}

DatabaseModel *
DatabaseTable::model() const
{
	return qobject_cast<DatabaseModel *>(scene());
}

QRectF
DatabaseTable::boundingRect() const
{
	return m_outerRect;
}

void
DatabaseTable::paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget)
{
	Q_UNUSED(option);
	Q_UNUSED(widget);

	QFont font = scene()->font();
	QFont boldFont = font;
	boldFont.setBold(true);
	QFont boldFontWithUnderline = boldFont;
	boldFontWithUnderline.setUnderline(true);

	QPen pen(QPen(QColor(0, 0, 0)));
	pen.setJoinStyle(Qt::MiterJoin);
	QPen borderPen(pen);
	if (isSelected()) {
		borderPen.setColor(QColor(0, 96, 255));
		borderPen.setWidth(2);
	}

	painter->setPen(pen);
	painter->setFont(font);

	painter->fillRect(m_outerRect, QColor(255, 255, 255));

	// Draw the table name
	painter->fillRect(m_nameBgRect, QColor(205, 205, 205));
	painter->drawLine(m_nameBgRect.bottomLeft(), m_nameBgRect.bottomRight());
	painter->drawText(m_namePos, m_name);
	
	painter->drawLine(
		m_leftSideWidth, m_nameBgRect.bottom(),
		m_leftSideWidth, m_outerRect.bottom());
	
	// Draw the table name
	QPointF colPos = m_firstColPos;
	QPointF leftSizePos = colPos - QPointF(m_leftSideWidth, 0);
	foreach (Column *column, m_columns) {
		painter->setFont(column->isRequired()
			? (column->isPrimaryKey() ? boldFontWithUnderline : boldFont)
			: font);
		painter->drawText(colPos, column->name());
		if (column->isPrimaryKey()) {
			painter->setFont(column->isRequired() ? boldFont : font);
			painter->drawText(leftSizePos, "PK");
		}
		colPos += m_colPosIncrement;
		leftSizePos += m_colPosIncrement;
	}
	
	// Draw the outside border
	painter->setPen(borderPen);
	painter->drawRect(m_outerRect);
}

void
DatabaseTable::setName(const QString &name)
{
	m_name = name;
	updateLayout();
	emit propertyChanged("name", name);
}

Column *
DatabaseTable::addColumn(const QString &name)
{
	Column *column = new Column(this);
	column->setName(name);
	m_columns.append(column);
	updateLayout();
	return column;
}

void
DatabaseTable::setColumn(int index, const QString &name)
{
	m_columns[index]->setName(name);
	updateLayout();
}

void
DatabaseTable::removeColumn(int index)
{
	delete m_columns.takeAt(index);
	updateLayout();
}

void
DatabaseTable::swapColumns(int index1, int index2)
{
	qSwap(m_columns[index1], m_columns[index2]);
	updateLayout();
}

QVariant
DatabaseTable::itemChange(GraphicsItemChange change, const QVariant &value)
{
	if (change == ItemSceneHasChanged) {
		updateLayout();
	}
	if (change == ItemPositionChange) {
		DatabaseModel *model = qobject_cast<DatabaseModel *>(scene());
		if (model) {
			emit model->tableMoved(this);
		}
	}
	return QGraphicsItem::itemChange(change, value);
}

void
DatabaseTable::updateLayout()
{
	if (!scene())
		return;

	prepareGeometryChange();

	QFont font = scene()->font();
	QFontMetricsF fontMetrics(font);

	QFont boldFont = font;
	boldFont.setBold(true);
	QFontMetricsF boldFontMetrics(boldFont);

	qreal spaceWidth = fontMetrics.width(' ');
	qreal nameWidth = fontMetrics.width(m_name);
	qreal height = fontMetrics.height();
	
	m_leftSideWidth = fontMetrics.width("PK");

	qreal width = nameWidth + spaceWidth * 2;

	qreal maxColumnWidth = 0;
	foreach (Column *column, m_columns) {
		qreal columnWidth = column->isRequired() ? boldFontMetrics.width(column->name()) : fontMetrics.width(column->name());
		maxColumnWidth = qMax(maxColumnWidth, columnWidth);
		qreal columnLeftSideWidth = 0;
		if (column->isPrimaryKey()) {
			if (column->isRequired()) {
				columnLeftSideWidth = boldFontMetrics.width("PK");
			}
			else {
				columnLeftSideWidth = fontMetrics.width("PK");
			}
		}
		m_leftSideWidth = qMax(m_leftSideWidth, columnLeftSideWidth);
	}
	m_leftSideWidth += spaceWidth * 2;
	width = qMax(nameWidth + spaceWidth * 4, m_leftSideWidth + maxColumnWidth + spaceWidth * 2);
	
	qreal nameHeight = height + spaceWidth;
	m_outerRect = QRectF(0, 0, width, nameHeight + qMax(0.66, qreal(m_columns.size())) * fontMetrics.lineSpacing()
		- fontMetrics.leading() + fontMetrics.descent());

	m_nameBgRect = QRectF(0, 0, width, nameHeight);
	m_namePos = QPointF((width - nameWidth) / 2, fontMetrics.ascent() + spaceWidth / 2);

	m_firstColPos = QPointF(m_leftSideWidth + spaceWidth * 1 - 1, nameHeight + fontMetrics.ascent() + 2);
	m_colPosIncrement = QPointF(0, fontMetrics.lineSpacing());

	update();
}